Scientists have captured a hum emitted by a star trillions of miles away as part of new research that is providing insights into what lies beneath the surface of stars. The harmonic hum, which sounds a little like wind blowing over a microphone, has revealed new information about the internal structure of the star, explained Bill Chaplin, asteroseismologist at Birmingham University.“Essentially stars resonate like a huge musical instrument. Stars make sounds naturally but we can’t hear this as it has to travel through space,” he said. “Like a musical instrument, stars are not uniformly solid all the way to their core, so the sound gets trapped inside the outer layers and oscillates around inside. “This makes the star vibrate, causing it to expand and contract. We can detect this visually because the star gets brighter and dimmer and so we can reconstruct the sounds produced from these vibrations.” Birmingham University astrophysicists, working with NASA scientists, have measured the changes in the brightness of light emanating from the star KIC 11026764, nicknamed Gemma and about twice the sun’s size. They found the star, 3,100 trillion miles away from the Earth, vibrates like a musical instrument owing to ‘starquakes’ that resonate from the surface to the core. Using a technique called astroseismology, they were able to detect the flickers of light caused by these starquakes and reconstruct the sound produced by the star, reports the Telegraph. The new research comes just six months after scientists at Sheffield University recorded eerie musical harmonies emitted from the surface of the sun. Chaplin worked with an international team using data captured by Nasa’s Kepler space telescope, which is searching for planets orbiting stars in our galaxy. In the same way as a cello produces a deeper note than a violin, the larger a star is the lower the frequency at which it vibrates, allowing scientists to calculate the size of a star. Using their measurements the astrophysicists calculated that Gemma is more than 5.94 billion years old, around a billion years older than the sun.